Thread: Help needed with code to display something similar to DIR

Hi, I am currently working on some code that will display all filenames, filesizes and starting inode number for the current directory (although i would like to change it so that the user can input a directory to display. Anyways here is my code...

Code:

#include <stdio.h>
#include <dirent.h>
#include <sys/stat.h>
#include <string.h>


int main() {


    //printf("file i-node example\n");


    DIR *currentDirectory;
    struct dirent *fileEntry;
    struct stat *file_stat;
    currentDirectory = opendir(".");
    printf("Name\tInode\tSize\n");
        if( currentDirectory != NULL ) {
            while( ( fileEntry = readdir( currentDirectory ) ) != NULL ) {
                printf( "%s\t%d\t%u\n", fileEntry->d_name, fileEntry->d_ino, file_stat->st_size );
            }
            closedir( currentDirectory );
        }
    return 1;
}

The issue that I am having is that the filesizes that are given are CRAZY!, here is a copy of the output...

Name Inode Size
test 262624 3506801480
coursework.c~ 265169 3506801480
test2.c 265163 3506801480
test2.c~ 265176 3506801480
coursetest.c 265044 3506801480
.. 262171 3506801480
dir_inode.c~ 265071 3506801480
a.out 262399 3506801480
main.c 262408 3506801480
dir_inode.c 265140 3506801480
. 262217 3506801480
coursework.c 265165 3506801480
test.c~ 265166 3506801480
test.c 265053 3506801480

Thanks for reading :-)

(I feel like it could be a stupid error that I have made as I have been staring at my screen for hours now!)

Wouldn't it be nice to actually call stat() on the file instead of printing out data from a random memory location?

If I knew how to do that I wouldn't be asking for advice. Thanks, ill look into that know, feel free to give a hint.

Originally Posted by CharlieCrawt

If I knew how to do that I wouldn't be asking for advice. Thanks, ill look into that know, feel free to give a hint.

He gave you a big hint.

Well, since you're on some sort of *nix platform, I suggest you check the man page: "man 2 stat" from the command line gives lots of great info, including an example.

thanks, im working through it now, if you cant tell i am new to programming.

One more thing: Generally you return 0 from main when your program completes successfully. Non-zero is typically for errors or special conditions. Alternatively, you can return the standard C EXIT_FAILURE or EXIT_SUCCESS, just remember to #include <stdlib.h>.

You've been told the answer twice! It's got nothing to with the printing, and everything to do with you not having the data you're looking for -- the size of the file!

Code:

struct stat *file_stat;

Where did you set file_stat to a valid location?

Tim S.

Remember how I told you back in post #5 to type "man 2 stat" at the terminal and read the man page and example? Do that. Notice how they actually call the stat() function, like rags_to_riches said you need to do back in post #2.

If you aren't clear on what a function call is or how to call a function in C yet, then this is probably not the best program for you to learn on. Find a simpler example of functions, then find one that includes passing parameters and checking return values. Learn how that works, then come back to this program.

I thought that This would be easier than I am finding it as I have made a whole game in C++ which was built off of many functions.

This is what I've gotten from the Pelles C help file on it:

_stat function [not standard C]

Purpose:
Retrieves file status.

Syntax:
int _stat(const char *name, struct _stat *info);

Declared in:
<sys/stat.h>

Description:
The _stat function retrieves information about the file or directory specified in the string pointed to by name, and stores the result in a _stat structure pointed to by info. The string pointed to by name may contain a full path (from the root), a relative path (from the current directory) or just a name.

Returns:
Zero on success, otherwise -1 and errno contains the error code.

What caught my eye is, it's not standard C, and I'm wondering what similar function (if any), would be standard C?